[PATCH 2/6] service: introduce per-lcore cycles counter

["Mattias Rönnblom" <mattias.ronnblom@ericsson.com>]

Introduce a per-lcore counter for the total time spent on processing
services on that core.

This counter is useful when measuring individual lcore load.

Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
---
 app/test/test_service_cores.c |  2 +-
 lib/eal/common/rte_service.c  | 14 ++++++++++++++
 lib/eal/include/rte_service.h |  6 ++++++
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/app/test/test_service_cores.c b/app/test/test_service_cores.c
index 7415b6b686..096405133b 100644
--- a/app/test/test_service_cores.c
+++ b/app/test/test_service_cores.c
@@ -403,7 +403,7 @@ service_lcore_attr_get(void)
 			"lcore_attr_get() failed to get loops "
 			"(expected > zero)");
 
-	lcore_attr_id++;  // invalid lcore attr id
+	lcore_attr_id = 42; /* invalid lcore attr id */
 	TEST_ASSERT_EQUAL(-EINVAL, rte_service_lcore_attr_get(slcore_id,
 			lcore_attr_id, &lcore_attr_value),
 			"Invalid lcore attr didn't return -EINVAL");
diff --git a/lib/eal/common/rte_service.c b/lib/eal/common/rte_service.c
index b5103f2a20..87df04e3ac 100644
--- a/lib/eal/common/rte_service.c
+++ b/lib/eal/common/rte_service.c
@@ -61,6 +61,7 @@ struct core_state {
 	uint8_t is_service_core; /* set if core is currently a service core */
 	uint8_t service_active_on_lcore[RTE_SERVICE_NUM_MAX];
 	uint64_t loops;
+	uint64_t cycles;
 	uint64_t calls_per_service[RTE_SERVICE_NUM_MAX];
 	uint64_t cycles_per_service[RTE_SERVICE_NUM_MAX];
 } __rte_cache_aligned;
@@ -372,6 +373,8 @@ service_runner_do_callback(struct rte_service_spec_impl *s,
 		 * is needed, and not the more expensive atomic
 		 * add.
 		 */
+		__atomic_store_n(&cs->cycles, cs->cycles + cycles,
+				 __ATOMIC_RELAXED);
 		__atomic_store_n(&cs->calls_per_service[service_idx],
 				 cs->calls_per_service[service_idx] + 1,
 				 __ATOMIC_RELAXED);
@@ -812,6 +815,14 @@ lcore_attr_get_loops(unsigned int lcore)
 	return __atomic_load_n(&cs->loops, __ATOMIC_RELAXED);
 }
 
+static uint64_t
+lcore_attr_get_cycles(unsigned int lcore)
+{
+	struct core_state *cs = &lcore_states[lcore];
+
+	return __atomic_load_n(&cs->cycles, __ATOMIC_RELAXED);
+}
+
 static uint64_t
 lcore_attr_get_service_calls(uint32_t service_id, unsigned int lcore)
 {
@@ -896,6 +907,9 @@ rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id,
 	case RTE_SERVICE_LCORE_ATTR_LOOPS:
 		*attr_value = lcore_attr_get_loops(lcore);
 		return 0;
+	case RTE_SERVICE_LCORE_ATTR_CYCLES:
+		*attr_value = lcore_attr_get_cycles(lcore);
+		return 0;
 	default:
 		return -EINVAL;
 	}
diff --git a/lib/eal/include/rte_service.h b/lib/eal/include/rte_service.h
index 35d8018684..70deb6e53a 100644
--- a/lib/eal/include/rte_service.h
+++ b/lib/eal/include/rte_service.h
@@ -407,6 +407,12 @@ int32_t rte_service_attr_reset_all(uint32_t id);
  */
 #define RTE_SERVICE_LCORE_ATTR_LOOPS 0
 
+/**
+ * Returns the total number of cycles that the lcore has spent on
+ * running services.
+ */
+#define RTE_SERVICE_LCORE_ATTR_CYCLES 1
+
 /**
  * Get an attribute from a service core.
  *
-- 
2.34.1